some Arabs, Ibn Ḥafṣūn took the side of the Emir. But as his supporters wearied of so temporising a policy, he imprisoned the commander of the Emir's army, and thus caused a complete rupture. Realising that he was virtually master of Spain and imagining that the Arabs and Berbers would refuse to yield him obedience, Omar entered into negotiations for his appointment as emir by the Abbasid Caliph, and through him came into touch with Ibn al-Aghlab, the emir of Africa. As Cordova was now in desperate straits, and his own position even worse, the Emir resolved to stake everything on a single cast, and with the approval of all his supporters attacked the enemy. On Thursday in Holy Week, 16 April 891, the battle began near the castle of Polei (now Aguilar). For the royalists the fortunes of the Umayyads were at stake and they fought desperately. They routed Ibn Ḥafṣūn, while 'Abdallāh sat in his tent and hypocritically recited verses from the Koran expressing his whole confidence in God. He then laid siege to Polei, and soon took it, pardoning the Muslims but slaying the Christians.
The result of the battle of Polei was the surrender of Écija, Archidona, Elvira and Jaen and the restoration of the Emir's authority; but their submission did not last long. In 892 Ibn Ḥafṣūn captured Archidona and Elvira; and to crown his success seized Jaen. In 893, however, he lost Elvira again; in 895 the Emir advanced against Seville, which Ḳuraib ibn Khaldūn successfully defended. Ibn Ḥajjāj, who became master of Seville, made his submission for a brief period and left his son 'Abd-ar-Raḥmān as a hostage in Cordova: shortly after he formed an alliance with Ibn Ḥafṣūn. Because he had become a Christian Omar had been deserted by many of his Muslin subjects, and he therefore gladly made a new confederacy with the Beni-Ḳasi of Saragossa and the king of Leon. The Emir's position was deplorable, though he succeeded in making peace with Ibn Ḥafṣūn (901). In 902 he renewed the war, which went against the allies. In hopes of detaching Ibn Ḥajjāj from the league 'Abdallāh handed over to him his son 'Abd-ar-Raḥmān. Ibn Ḥajjāj was grateful and was reconciled with the Emir. 'Abdallāh advanced from one victory to another. He captured Jaen, and seemed to have greatly improved his position, when he died on 15 October 912.
When 'Abd-ar-Raḥmān III, 'Abdallāh's grandson, ascended the throne of the Umayyads, he found Muslim Spain rent by civil war and menaced by two enemies from outside, the kingdom of Leon and the Fātimite Caliphate in Africa. The latter had been founded by the Ismaelites, who were one of the Shī'ite sects, and aimed at forcing their way into Spain, through the preaching of the Mahdī or secret Imām, with the object of establishing a universal monarchy. One of the tools employed by the Fātimites seems to have been Ibn Masarra, a philosopher at Cordova. But though he had made proselytes among the common people, he had failed to obtain a following among the faḳīhs, and his books were burnt as heretical. The kingdom of Leon,
